-transparent.png){kind=logo}
The kinetic profile and half-life of naloxone were studied for possible use in determination of pA2 and KB in vivo. Rats were given morphine subcutaneously and after 15 min naloxone or saline, intracerebroventricularly. A further 15 min later, and at 15 min intervals up to 135 min after morphine, the animals were tested for analgesia in the tail flick test. The dose-response curves of the naloxone group were shifted to the right of those for the saline group. The amount of displacement decreased with time, indicative of the disappearance of naloxone. The graph of log (dose ratio-1) vs. time was linear with negative slope, in agreement with the time-dependent form of the equation for competitive antagonism. From this slope, the half-life of naloxone was calculated to be 13.3 min. These results demonstrate that the time-dependent method is useful in obtaining the kinetics of centrally acting opiate antagonists.
F Porreca, and
A Cowan, and
R J Tallarida
June 1991,
Indian journal of experimental biology,
F Porreca, and
A Cowan, and
R J Tallarida
June 1993,
The Journal of pharmacology and experimental therapeutics,
F Porreca, and
A Cowan, and
R J Tallarida
December 1976,
Research communications in chemical pathology and pharmacology,
F Porreca, and
A Cowan, and
R J Tallarida
March 1991,
The Journal of pharmacology and experimental therapeutics,
F Porreca, and
A Cowan, and
R J Tallarida
April 1992,
The Journal of pharmacology and experimental therapeutics,
F Porreca, and
A Cowan, and
R J Tallarida
December 1999,
Neuropeptides,
F Porreca, and
A Cowan, and
R J Tallarida
January 1971,
Anesthesia and analgesia,
F Porreca, and
A Cowan, and
R J Tallarida
May 1994,
Neuropeptides,
F Porreca, and
A Cowan, and
R J Tallarida
November 1997,
General pharmacology,
F Porreca, and
A Cowan, and
R J Tallarida
April 1996,
Neuropeptides,
